632024 - Reflect.parse(Array(1000).join("x + y - ") + "z") crashes with stack overflow

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Jason Orendorff [:jorendorff]]

js_EmitTree can't compile that expression either, but it manage to avoid crashing by calling JS_CHECK_RECURSION.

Comment 1

[Dave Herman [:dherman]]

Couldn't reproduce on my MacOS machine at first, but fattening up my ASTSerializer::expression() frames with a 16KB array got it to reproduce, using

    Reflect.parse(Array(195).join("x + y - ") + "z")

Dave

Comment 2

[Dave Herman [:dherman]]

I need to audit this a little more carefully, but I think the main recursive entry points that need a JS_CHECK_RECURSION guard are:

    ASTSerializer::expression()
    ASTSerializer::statement()
    ASTSerializer::pattern()

and possibly

    ASTSerializer::declaration()

That last one may not be necessary. I'll post a patch soon.

Thanks,
Dave

Comment 3

[Dave Herman [:dherman]]

Attachment: ohai JS_CHECK_RECURSION

Jason, if you have a chance could you test this patch on your Windows machine? I will also run it through tryserver.

Thanks,
Dave

Comment 4

[Dave Herman [:dherman]]

BTW, the patch adds JS_CHECK_RECURSION for the following entry points:

    ASTSerializer::expression()
    ASTSerializer::statement()
    ASTSerializer::pattern()
    ASTSerializer::xml()

It doesn't for ASTSerializer::declaration() or ASTSerializer::function() since those can only enter cycles by passing through ASTSerializer::statement() or ASTSerializer::expression().

Dave

Comment 5

[Dave Herman [:dherman]]

Attachment: refreshed stale patch

Patch had gone stale; updated.

Jason: can you test this for me on your Windows machine?

Thanks,
Dave

Comment 6

[Jason Orendorff [:jorendorff]]

Comment on attachment 537796 [details] [diff] [review]
refreshed stale patch

Review of attachment 537796 [details] [diff] [review]:
-----------------------------------------------------------------

Comment 7

[Jason Orendorff [:jorendorff]]

It works on my machine.

js> Reflect.parse(Array(1000).join("x + y - ") + "z")
typein:1: InternalError: too much recursion

Comment 8

[Dave Herman [:dherman]]

http://hg.mozilla.org/tracemonkey/rev/0cc25c98d38e

Comment 9

[Chris Leary [:cdleary] (not checking bugmail)]

cdleary-bot mozilla-central merge info:
http://hg.mozilla.org/mozilla-central/rev/0cc25c98d38e